AB1493 ADULT ONSET STILL’S DISEASE: ANALYSIS OF A MONOCENTRIC COHORT
Authors: P. Migliorini, D. Testa, S. Bilia, A. Tavoni
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Adult onset Still's disease (AOSD) is a systemic autoinflammatory disorder, sustained by a persistent inflammasome activation with the production of high amounts of IL-1beta and IL-18. Due to the rarity of the disorder, few multicentric cohorts of patients have been so far described. <h3>Objectives</h3> To analyze clinical manifestations, disease course, treatments and response to therapy in a monocentric cohort of AOSD patients. <h3>Methods</h3> We conducted a retrospective analysis of a cohort of consecutive patients, diagnosed as AOSD in our unit according to Yamaguchi and/or Faultrel criteria. Clinical data and therapeutic approach were analyzed; disease severity was scored by means of Pouchot score. Data were analyzed by multivariate analysis (partial least square model). <h3>Results</h3> We enrolled 40 patients (21 males, 19 females), mean age 63 yrs (range 21-88), age at disease onset 48 yrs. Fever and arthralgia were present in all the patients, in 77% rash, in 60% sore throat and lymphadenopathy, in 50% hepatosplenomegaly. At disease onset, 5 had intravascular disseminated coagulopathy, 4 acute respiratory distress and 2 myocarditis. In all the patients acute phase reactants were markedly increased and ferritin levels were elevated. Patients were followed for average 6,3 yrs (range 1-16 yrs): 10 patients had a monocyclic pattern, 14 polycyclic, 16 chronic articular. Mean relapses/patient were 3,8; 26% showed &gt;5 relapses and 7% &gt; 25. Chronic articular pattern is the only variable that predicts the number of relapses (p=0,001). Mean Pouchot score at disease onset was 5,5 (&gt;7 in 15 patients); it decreased to 2,2 after 6 months and was 1,2 at the last follow up visit. All the patients were treated with steroids (pulses in 18%), mean steroid dose/patient 9,6 gr. Steroids only were used in 5% of the patients, csDMARDS in 22,5% of the patients (MTX in 60%, Csa in 15%), biologicals in 72,5% (Anakinra in 62%; Tocilizumab in 28%). In 40% of the patients, steroid and one cs or bDMARD allowed to achieve disease control. In 60% one or more therapeutic switches were necessary, because of lack/loss of efficacy or adverse drug reactions. Drug retention rate was 76% at 6 months, 40% at 3 yrs and 4 yrs for Anakinra; 91% at 6 months and 36% at 5 yrs for Tocilizumab. In one patient out of 25 treated with Anakinra and in 3 out of 11 treated with Tocilizumab, the therapy was discontinued for persistent clinical remission. <h3>Conclusion</h3> The data we collected confirm the severity and the multisystem involvement of AOSD in a monocentric cohort with a long follow up. Among the different clinical patterns, the chronic articular one is associated with more frequent flares. Severe manifestations of the disease were present at disease onset but did not appear thereafter, suggesting the efficacy of drug therapy and close follow up. Inhibition of IL-1 and IL-6 is a safe and effective therapy. Persistent clinical remission that allows withdrawal of therapy can be obtained albeit in a small number of cases. <h3>References</h3> [1]Fautrel B. et al Proposal for a new set of classification criteria for adult-onset Still disease. Medicine (Baltimore) 2002;81:194-200 [2]Yamaguchi M. et al Preliminary criteria for classification of adult Still's disease. J Rheumatol 19(3):424-430 [3]Ruscitti P. et al. Adult Onset Still Disease: evaluation of prognostic tools and validation of the systemic score by analysis of 100 cases from three centers. 2016 BMC Med 14:194 <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> None Declared.